By September the book was going well – 30,000 words done. A Christmas deadline loomed. I was writing a chapter on the NSA’s close, and largely hidden, relationship with Silicon Valley. I wrote that Snowden’s revelations had damaged US tech companies and their bottom line. Something odd happened. The paragraph I had just written began to self-delete. The cursor moved rapidly from the left, gobbling text. I watched my words vanish. When I tried to close my OpenOffice file the keyboard began flashing and bleeping.

Over the next few weeks these incidents of remote deletion happened several times. There was no fixed pattern but it tended to occur when I wrote disparagingly of the NSA. All authors expect criticism. But criticism before publication by an anonymous, divine third party is something novel. I began to leave notes for my secret reader. I tried to be polite, but irritation crept in. Once I wrote: “Good morning. I don’t mind you reading my manuscript – you’re doing so already – but I’d be grateful if you don’t delete it. Thank you.” There was no reply. A month later the mysterious reader – him, her, they? – abruptly disappeared. …

In idle moments I wonder who might have been my surreptitious editor. An aggrieved analyst at the NSA’s Fort Meade spy city? GCHQ? A Russian hacker? Someone else intent on mischief? Whoever you are, what did you think of my book? I’d genuinely like to know.

Update from a reader:

Luke Harding’s story of remote censorship reeks of dishonesty. If I was writing something and someone showed that they had access to my computer I’d immediately, physically disconnect it from the internet and then back up my work before wiping it and putting a clean install of the OS back on it. After that I’d certainly continue my work unconnected from the internet. That Mr. Harding claims to have put up with this for an extended period of time shows he’s either a moron or a fabulist.

David Blair gave Harding’s book a two-star review, saying the prose “lapses into the breathless style of an airport blockbuster”:

Harding’s story crackles with verve, but complexity and nuance are banished. In particular, the real dilemmas of intelligence work are ignored. If GCHQ and the NSA share everything, they risk Snowden-style breaches. If they restore pre-9/11 restrictions, then vital information that might prevent attacks is bottled up. If the agencies store data, they are accused of threatening privacy; if they do not, then the communications of terrorists simply vanish. Harding considers none of this; only when Snowden flies to Russia does he voice any unease.

Reviewing the book earlier this month, Michiko Kakutani was less harsh (NYT):

Portions of “The Snowden Files” seem particularly aimed at a British audience, focusing at length on the surveillance activities of the GCHQ and its eager-to-please relationship with its wealthy American counterpart. But the book still gives readers, who have not been following the Snowden story closely, a succinct overview of the momentous events of the past year. And if it leans toward dramatizing everything in thrillerlike terms, the book also manages to leave readers with an acute understanding of the serious issues involved: the N.S.A.’s surveillance activities and voluminous collection of data, and the consequences that this sifting of bigger and bigger haystacks for tiny needles has had on the public and its right to privacy.